Accelerating Cyclic Loading

Abstract

In this work, we performed four variations of cyclic load testing on four groups of modules using the LoadSpot tool. Each group first underwent 50 thermal cycles (TC50), 10 humidity-freeze cycles (HF10), and a 2400 Pa static load. Then, the baseline group was tested using standard cyclic loading conditions from IEC 62782, another with double the loading frequency, one with larger loading magnitude, and one with smaller loading magnitude and quadruple the loading frequency. Interestingly, we found that increasing the loading frequency actually reduces maximum power degradation with respect to the baseline, whereas increasing or decreasing the load amplitude respectively increases or decreases maximum power degradation with respect to the baseline. In order to confirm the results, we conducted another experiment with a new group using modules of a different make and model. This group did not undergo TC50 nor HF 10, only a 5400Pa static load to create cracks. For this group, the maximum power degradation did not show a dependence on the loading frequency during cyclic loading. We offer a possible explanation for this unexpected result associated with increasing the loading frequency.